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A comment on Unveiling the first-ever image of a black hole [video]. Parent comment

Re:Unveiling the first-ever image of a black hole [video] by Abishek_Muthian on Thursday April 11, 2019 @02:17AM (#19631623)
In the video he talks about the Schwarzchild radius but doesn't go into details. It is the distance from the center of the black hole to the event horizon.

Anything which is not in that radius or not already in a path towards it should be safe from not getting sucked by the black hole.

E.g. If our sun becomes a black hole, Schwarzchild radius would be 2.954Km i.e. anything outside ~3Km would be safe.

This was explained in the scishow video on that topic[1].

[1]:https://youtu.be/Mm_ks1ce3C4

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Re:Unveiling the first-ever image of a black hole [video] by ben_w on Thursday April 11, 2019 @03:34AM (#19631921)
That’s an oversimplification. The Schwarzschild radius is where to find an uncharged & non-rotating black hole’s event horizon, and the event horizon is the surface at which newly generated photos (and all causal influences) can no longer escape.

The innermost stable circular orbit is further out than the event horizon, 3 times the Schwarzschild radius IIRC. Anything closer to that has an unstable orbit.

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